Item comes fully certified with a tamper-evident, serialized hologram and certificate of authenticity.
Ron Guidry autographed baseball card (New York Yankees) 2006 Fleer Greats of the Game #80
Ranking the Top 10 Pitchers in Yankees and Red Sox History
Yankees legend Ron Guidry makes special appearance in Somerset
Ron Guidry, Ft. Lauderdale Yankee Stadium, Ft. Lauderdale, Florida
Ron Guidry's 18-strikeout performance in 1978
Did You Get In? The Night NYY's Ron Guidry Took Over Albany
Retro Baseball 101 - Ron Guidry, of the New York Yankees, set an
Ron Guidry Autographed Official Major League Baseball Inscribed
Ron Guidry – Society for American Baseball Research
Ron Guidry, Baseball Wiki